OBJECTIVE: To investigate the genetic mechanism for adverse pregnancies due to submicroscopic chromosomal structural variants in two cases, and to provide a precise guidance for preimplantation genetic testing. METHODS: Two families who had visited Chengdu Women's and Children's Central Hospital for reproduction guidance due to recurrent miscarriages, adverse pregnancy history and abnormal genetic testing of the offspring in June and December 2023 were selected as the study subjects. Chromosomal karyotyping and optical genome mapping (OGM) were carried out on peripheral blood samples from the two couples, and preimplantation genetic testing for structural rearrangement (PGT-SR) were performed on the blastocyst trophoblasts. This study was approved by the Medical Ethics Committee of the Hospital (Ethic No.: 2023-23). RESULTS: No abnormality was found on the G-banded karyotyping analysis for both couples. The OGM results revealed that the female partner of couple 1 had a translocation between 4pter-p16.3 (3.99 Mb) and 11pter-p15.4 (2.66 Mb), whilst no abnormality was found in the male partner. Similarly, the male partner of couple 2 had a translocation between 19q13.43-qter (1.90 Mb) and 22q13.31-qter (3.34 Mb). No abnormality was found in the female partner of couple 2. Neither breakpoints nor the adjacent region had involved an OMIM gene, except the formation of a fusion gene ZIM2-AS1-Z82186.1 (Both genes are non-coding, and the fusion gene was deemed as variant of unknown significance). PGT-SR of 11 blastocysts derived from couple 1 revealed that one embryo was suitable for priority transfer, three embryos were suitable for transfer, one embryo was recommended for genetic counselling, and six embryos were unsuitable for the transfer. For couple 2, six blastocysts were tested, of which only one embryo was deemed suitable for transfer. CONCLUSION When genetic testing of offspring indicates copy number variations such as deletions, duplications or mosaicism, the high-resolution OGM technique can be selected to screen parents for submicroscopic chromosomal structural variations. The result can facilitate accurate assessment for the risk of recurrence in offspring, selection of suitable method for reproduction, and identifying targets for PGT.
Humans ; Female ; Pregnancy ; Adult ; Male ; Karyotyping ; Chromosome Aberrations ; Abortion, Habitual/genetics* ; Preimplantation Diagnosis ; Genetic Testing

OBJECTIVE: To investigate the current status of clinical genetics specialization development and the diagnostic and therapeutic capabilities for hereditary diseases across medical institutions in Shanghai, and to assess the necessity and feasibility of establishing training bases for clinical genetics specialists. METHODS: By employing a cross-sectional survey design, the Clinical Genetics Committee of Shanghai Medical Association has conducted questionnaire surveys from March to April 2025 across 54 healthcare institutions in Shanghai (including 33 tertiary hospitals and 21 secondary hospitals). The survey involved administrative departments and medical personnel from 15 clinical specialties. The survey has covered current genetic disease diagnosis and treatment practices, relevant and specialised disease types, genetic department establishment, testing capabilities, personnel teams, and training requirements. RESULTS: The results revealed that 78.0% of clinical departments surveyed had treated patients with hereditary disorders. Shanghai possesses diagnostic and therapeutic expertise for over 95% of hereditary diseases listed in its rare disease catalogue, reflecting both the practical clinical demand for such conditions and the city's overall diagnostic and therapeutic strengths in this field. Nevertheless, significant disparities exist in the development of genetics departments across different tiers of healthcare institutions. Resources for genetic testing capabilities (including molecular, cellular, and biochemical testing) are also unevenly distributed across different tiers of hospitals. The survey further revealed that only 26.0% of departments believe that their current physician structure fully meets the diagnostic and treatment demands. Over 90% of departments consider standard training for clinical genetic specialists necessary, with 74.0% expressing willingness to participate in establishing training bases. Based on above findings and thorough deliberation, the Clinical Genetics Committee of the Shanghai Medical Association proposes advancing specialist training and discipline development through establishing a standard training system. The committee has drafted a three-year training protocol featuring a "joint training"-centered model, recommending a pilot-first, dynamically optimized strategy for steadily advancing training base development. CONCLUSION Shanghai faces substantial demand for genetic disease diagnosis and treatment, yet exhibits shortcomings in clinical genetics specialization development, resource allocation, and talent pipeline cultivation. To establish a standard training system holds significant practical importance and is underpinned by a broad demand.
Humans ; China ; Surveys and Questionnaires ; Genetic Diseases, Inborn/genetics* ; Cross-Sectional Studies ; Genetics, Medical/education* ; Genetic Testing

OBJECTIVE: To explore the genetic etiology of 46 Chinese pedigrees affected with Hereditary multiple exostoses (HME) and provide genetic counseling and reproductive intervention. METHODS: Whole-exome sequencing and Sanger sequencing were carried out on 87 patients from the 46 pedigrees to analyze the variants of EXT1 and EXT2 genes. Pathogenicity of the variants was assessed based on the guidelines from the American College of Medical Genetics and Genomics and Association for Molecular Pathology (ACMG/AMP). Prenatal diagnosis and preimplantation genetic testing (PGT) were provided for couples with identified pathogenic mutations. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: LL-SC-SG-2014-010). RESULTS: In total 17 and 22 pathogenic variants were respectively identified in the EXT1 and EXT2 genes, among which 5 EXT1 and 12 EXT2 variants were unreported previously. Three patients with no family history were found to harbor de novo variants of the EXT1 gene. Twenty nine couples had opted for PGT or underwent prenatal diagnosis following natural conception, and 17 healthy babies were born. CONCLUSION This study has clarified the genetic etiology of 45 HME pedigrees and identified 17 novel variants, which has enriched the mutational spectrum of the EXT1 and EXT2 genes. Reproductive intervention through PGT and prenatal diagnosis have prevented the recurrence of HME in these families.
Humans ; Female ; Male ; Pedigree ; Exostoses, Multiple Hereditary/diagnosis* ; N-Acetylglucosaminyltransferases/genetics* ; Adult ; Exostosin 1 ; Asian People/genetics* ; Genetic Testing ; Exostosin 2 ; Mutation ; China ; Prenatal Diagnosis ; Pregnancy ; Genetic Counseling ; Preimplantation Diagnosis ; Exome Sequencing ; East Asian People

OBJECTIVE: To explore the efficacy of a Thalassemia risk assessment software for the screening of thalassemia mutation carriers and distribution of thalassemia genotypes detected by screening. METHODS: A total of 6 040 individuals were evaluated at Leshan Maternal and Child Health Care Hospital between 2022 and 2024 using the commonly used clinical thalassemia risk assessment method and the thalassemia screening software, respectively, and the performance indicators of the two methods were compared and analyzed against the result of thalassemia gene testing. This study was approved by the Ethics Committee of our hospital (Ethics No.: LfyLL[2022]005). RESULTS: The high-risk rate by the thalassemia screening software was 11.19%, with a sensitivity of 95.12%, specificity of 93.28%, positive predictive value of 43.20%, negative predictive value of 99.72%, and the area under the ROC curve (AUC) was 0.942. The thalassemia gene detection rate of the high-risk samples screened was 4.83%. The high-risk screening rate of the conventional method was 2.50%, with a sensitivity of 51.22%, specificity of 93.28%, positive predictive value of 80.79%, negative predictive value of 97.40%, and the AUC was 0.754. The thalassemia gene detection rate of the high-risk samples was 2.02%. CONCLUSION The software can effectively detect thalassemia carriers and significantly reduce the missed detection compared with conventional method, thereby significantly improve the efficacy of screening.
Humans ; Thalassemia/diagnosis* ; Software ; Female ; Genetic Testing/methods* ; Male ; Mutation ; Adult ; Genotype ; ROC Curve ; Risk Assessment

OBJECTIVES: To evaluate the clinical value of next-generation sequencing (NGS) in neonatal disease screening, particularly its advantages when combined with tandem mass spectrometry (MS/MS). METHODS: A prospective study was conducted involving blood samples from 1 999 neonates born at the Shenzhen Guangming District People's Hospital, between May and August 2021. All samples were initially screened using MS/MS and fluorescence immunoassay, followed by NGS to detect high-frequency variation sites in 135 related pathogenic genes. Suspected positive variants were validated using Sanger sequencing or multiplex ligation-dependent probe amplification in family studies. RESULTS: No confirmed positive cases were found in the MS/MS analysis of the 1 999 neonates. Genetic screening identified 58 positive cases (2.90%), 732 carriers of pathogenic genes (36.62%), and 1 209 negative cases (60.48%). One case of neonatal intrahepatic cholestasis was diagnosed (0.05%, 1/1 999). Fluorescence immunoassay identified 39 cases of glucose-6-phosphate dehydrogenase (G6PD) deficiency (1.95%, 39/1 999), while genetic screening identified 43 cases of G6PD deficiency (2.15%, 43/1 999). The fluorescence immunoassay also detected 6 cases of hyperthyrotropinemia (0.30%, 6/1 999), all of whom carried DUOX2 gene variants. The top ten pathogenic gene carrier rates were G6PD (12.8%), DUOX2 (8.7%), HBB (8.2%), ATP7B (6.6%), GJB2 (5.7%), SLC26A4 (5.6%), PAH (5.6%), ACADSB (4.6%), SLC25A13 (4.2%), and SLC22A5 (4.1%). CONCLUSIONS NGS can serve as an effective complement to MS/MS, significantly improving the detection rate of inherited metabolic disorders in neonates. When combined with family validation, it enables precise diagnosis, particularly demonstrating complementary advantages in screening for monogenic diseases such as G6PD deficiency.
Humans ; Infant, Newborn ; High-Throughput Nucleotide Sequencing/methods* ; Neonatal Screening/methods* ; Tandem Mass Spectrometry ; Prospective Studies ; Female ; Male ; Infant, Newborn, Diseases/diagnosis* ; Genetic Testing

OBJECTIVES: To evaluate the application value of genetic newborn screening (gNBS) in the Yunnan region. METHODS: A prospective study was conducted with a random selection of 3 001 newborns born in the Yunnan region from February to December 2021. Traditional newborn screening (tNBS) was used to test biochemical indicators, and targeted next-generation sequencing was employed to screen 159 genes related to 156 diseases. Positive-screened newborns underwent validation and confirmation tests, and confirmed cases received standardized treatment and long-term follow-up. RESULTS: Among the 3 001 newborns, 166 (5.53%) were initially positive for genetic screening, and 1 435 (47.82%) were genetic carriers. The top ten genes with the highest variation frequency were GJB2 (21.29%), DUOX2 (7.27%), HBA (6.14%), GALC (3.63%), SLC12A3 (3.33%), HBB (3.03%), G6PD (2.94%), SLC25A13 (2.90%), PAH (2.73%), and UNC13D (2.68%). Among the initially positive newborns from tNBS and gNBS, 33 (1.10%) and 47 (1.57%) cases were confirmed, respectively. A total of 48 (1.60%) cases were confirmed using gNBS+tNBS. The receiver operating characteristic curve analysis demonstrated that the areas under the curve for tNBS, gNBS, and gNBS+tNBS in diagnosing diseases were 0.866, 0.982, and 0.968, respectively (P<0.05). DeLong's test showed that the area under the curve for gNBS and gNBS+tNBS was higher than that for tNBS (P<0.05). CONCLUSIONS gNBS can expand the range of disease detection, and its combined use with tNBS can significantly shorten diagnosis time, enabling early intervention and treatment.
Humans ; Infant, Newborn ; Neonatal Screening ; Genetic Testing ; Female ; Male ; Follow-Up Studies ; Prospective Studies ; China

OBJECTIVE: To investigate the gene carrier rate and genotype distribution characteristics of thalassemia in the population of Kunming, and compare the differences of red blood cell (RBC) parameters between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy population, as well as between different sexes of adults aged 18-45 years. METHODS: A retrospective analysis of 3 195 cases of thalassemia gene screened in the First Affiliated Hospital of Kunming Medical University from April 1, 2020 to March 31, 2022 was performed to detect 21 mutations of β-globin genes which was common in Chinese people using fluorescence PCR melting curve method. Patients with single heterozygous carrying β-thalassemia gene were divided into β⁺ heterozygote group and β⁰ heterozygote group, while the control group consisted of 219 healthy individuals. Four indices, including RBC, hemoglobin (Hb), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were collected from all β heterozygous carriers and 219 healthy people, and compared between β⁺ heterozygote group, β⁰ heterozygote group and control group, as well as between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy population of different sexes aged 18-45 years. RESULTS: There were 688 cases confirmed thalassemia gene carriers, accounting for 21.53%. Among them, 322 cases were found to have β-globin gene mutations, including 145 cases of β⁺ heterozygote, 151 cases of β⁰ heterozygote, and 14 cases of β⁺ homozygotes as well as β⁺ and β⁰ dual heterozygotes. Additionally, 12 cases were found to have simultaneous mutation or deletion of β-globin and α-globin. The carrier rate of CD26 G>A mutation in β⁺ thalassemia was the highest, accounting for 57.9%, while in β⁰ thalassemia CD17 A>T was the highest, accounting for 46.4%. The erythrocyte parameters of 296 β heterozygous mutation carriers were compared with the normal reference interval, and it was found that 218 cases with RBC value greater than the highest value of reference interval, while 105, 281, and 269 cases with Hb, MCV, and MCH value less than the lowest value of reference interval, respectively. There were significant differences in the 4 erythrocyte parameters between β⁺ heterozygotes, β⁰ heterozygotes and healthy individuals (all P < 0.001), and further comparison between different sexes also showed significant differences (all P < 0.001). CONCLUSIONS The carrier rates of thalassemia gene and β-thalassemia heterozygote are both at high level in Kunming, and there are significant differences in the erythrocyte parameters between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy individuals. When genetic counseling, it is necessary to inform and strengthen screening among adults of marriageable age to prevent birth of children with severe thalassemia.
Humans ; beta-Thalassemia/blood* ; Adult ; Heterozygote ; Male ; Female ; beta-Globins/genetics* ; Retrospective Studies ; Middle Aged ; Mutation ; Adolescent ; Genotype ; Erythrocytes ; Erythrocyte Indices ; Young Adult ; China ; Genetic Testing ; Asian People/genetics*

OBJECTIVE: To investigate the common genotypes and distribution characteristics of thalassemia in Guiyang region, and preliminarily analyze the rare mutations of globin genes in this area. METHODS: A total of 9 334 individuals who came to our hospital for thalassemia screening from June 2016 to February 2023 were included in this study. They were examined for common thalassemia mutations using PCR-based flow-through hybridization technology. Meanwhile, rare and unknown mutations were detected by Sanger sequencing. RESULTS: Among the 9 334 cases, 895 positive cases of common thalassemia were detected, with a positive rate of 9.59%. Among the positive samples, 565 cases (63.13%) were confirmed to be α thalassemia, of which the most common genotypes were αα/-α^3.7 (46.37%), followed by αα/--^SEA(26.55%) and αα/-α^4.2(10.62%); 310 cases (34.64%) were diagnosed as β thalassemia, with β^CD17/β^N (39.35%) being the most frequent genotype, followed by β^CD41-42 /β^N (31.29%) and β ^IVS-II-654/ β^N (12.90%). There were 20 cases (2.23%) of αβ complex thalassemia, mainly being αα/-α^3.7 combined with β^CD17 /β^N . Additionally, 8 cases of rare globin gene mutations were found by Sanger sequencing, including 7 mutation types. Among them, HBB: c. -137C> T (-87 C>T) was reported for the first time in Guizhou; HBA1 : c.*29C>T and HBB : c. 93-50C>T (IVS I-81C>T) were new mutations that had not been recorded in either the HbVar or IthaGenes database. CONCLUSION Guiyang region has a high incidence of thalassemia mutations, and these mutations are diverse and complex. Analyzing gene mutation types of thalassemia in this area can contribute to the prevention of the birth of children with severe thalassemia.
Humans ; Genotype ; Mutation ; beta-Thalassemia/genetics* ; alpha-Thalassemia/genetics* ; Thalassemia/epidemiology* ; Genetic Testing ; China/epidemiology* ; Male ; Female

OBJECTIVE: To assess the feasibility of first polar body transfer (PB1T) combined with preimplantation mitochondrial genetic testing for blocking the transmission of a pathogenic mitochondrial DNA 8993T>G mutation. METHODS: A Chinese family affected with Leigh syndrome which had attended the Reproductive Medicine Centre of the First Affiliated Hospital of Anhui Medical University in September 2021 was selected as the study subject. Controlled ovarian hyperstimulation was carried out for the proband after completing the detection of the mitochondrial DNA 8993T>G mutation load among the pedigree members. Mature MII oocytes were inseminated by intracytoplasmic sperm injection (ICSI), cultured in vitro for 5 to 6 days to the blastocyst stage, and trophoblastocytes were obtained by microbiopsy. Mitochondrial DNA testing (PGT-MT) and chromosomal aneuploidy (PGT-A) analyses were carried out after whole-genome amplification, and the embryos with zero mutation load were selected for transfer. Amniotic fluid and umbilical cord blood samples were collected during middle pregnancy and after birth respectively for mitochondrial DNA testing to verify the reliability of embryo screening. As an attempt, PB1 with good morphology of MII oocytes was selected for transfer into the enucleated oocytoplasm from healthy donors, followed by ICSI fertilization, blastocyst culture and PGT of embryos using the same procedure. This study has been approved by the Ethics Committee of the First Affiliated Hospital of Anhui Medical University (No. 2021zhyx-B12). RESULTS: An antagonist protocol was used for ovarian stimulation, and a total of 19 oocytes were obtained, of which 14 MII were fertilized by ICSI, and 2 had developed into blastocysts. PGT-MT was carried out on biopsied trophoblastocytes, in which the mitochondrial DNA 8993T>G mutation load was not detected in one embryo, the other was 100% mutated, and the mutation loads of the remaining unfertilized eggs and developmentally arrested embryos ranged from 0% ~ 100%, presenting a clear biased distribution. With fully informed consent, one PGT-MT zero mutation load blastocyst was transferred and clinical pregnancy was achieved. Mitochondrial DNA and chromosomal testing of amniotic fluid cells during middle pregnancy had revealed no abnormalities. The proband had delivered a healthy boy through Caesarean section at 39⁺⁵ weeks of gestation, and no mutation was detected in the cord blood sample. Five well-formed PBs from 14 eggs were selected for PB1 transfer, followed by ICSI and culture, and two of the reconstituted embryos had formed blastocysts, with none of the above mutations detected in the biopsied samples. CONCLUSION The PGT-MT technology can help families affected with mitochondrial diseases to have healthy offspring. PB1 transfer in combination with ICSI and PGT-MT holds the promise of turning waste into treasure and providing an alternative means of fertility for such families.
Humans ; Preimplantation Diagnosis/methods* ; Female ; DNA, Mitochondrial/genetics* ; Genetic Testing/methods* ; Pregnancy ; Mitochondrial Diseases/genetics* ; Polar Bodies ; Adult ; Feasibility Studies ; Sperm Injections, Intracytoplasmic/methods* ; Embryo Transfer/methods* ; Mutation ; Male ; Blastocyst/metabolism* ; Pedigree

OBJECTIVE: To explore the results of four types of Urea cycle disorders (UCDs) in newborns from the Xuzhou region, assess the efficacy of newborn screening by tandem mass spectrometry (MS/MS), and analyze their genetic characteristics. METHODS: A retrospective analysis was performed using tandem mass spectrometry to screen for inherited metabolic disorders in 691 712 newborns at the Maternal and Child Health Care Hospital of Xuzhou from November 2015 to December 2023. Ten children (cases 1-10) were diagnosed with Ornithine transcarbamylase deficiency (OTCD), Carbamoylphosphate synthase 1 deficiency (CPS1D), Arginase deficiency (ARGD), and Argininosuccinate synthase deficiency (ASSD) based on MS/MS and genetic testing. This study was approved by the Medical Ethics Committee of Xuzhou Maternity and Child Health Care Hospital (Ethics No.XZFY2024-051K-01J). RESULTS: A total of 691 712 neonates were screened for UCDs using MS/MS, which identified 1 237, 1 237, 510, and 1 009 initial positive cases for OTCD, CPS1D, ASSD, and ARGD, respectively. After genetic testing, 1 case of OTCD, 1 case of CPS1D, 1 case of ASSD, and 7 cases of ARGD were confirmed. The overall positive predictive value for these four UCDs was 0.362%. Among the 10 diagnosed UCD cases, four novel variants were identified, which included OTC: c.1024C>A (p.L342M) and ASS1: c.826A>G (p.M276V), c.695C>T (p.P232L) and c.694C>T (p.P232S). Bioinformatic analysis has rated these as variants of uncertain clinical significance or likely pathogenic based on guidelines from the American College of Medical Genetics and Genomics (ACMG). CONCLUSION The incidence of four UCDs in neonates from the Xuzhou area is relatively low, and there is a correlation between genetic variants and clinical phenotypes. For novel variants with uncertain clinical significance or suspected pathogenicity, their pathogenicity should be clarified in conjunction with clinical and biochemical indicators. The four novel pathogenic variants of UCDs identified in this study have enriched the mutational spectrum of UCDs-associated genes in the Xuzhou region.
Humans ; Infant, Newborn ; Tandem Mass Spectrometry/methods* ; Urea Cycle Disorders, Inborn/diagnosis* ; Neonatal Screening/methods* ; Genetic Testing/methods* ; Female ; Retrospective Studies ; Male ; Ornithine Carbamoyltransferase Deficiency Disease/diagnosis* ; Mutation ; Carbamoyl-Phosphate Synthase (Ammonia)/genetics* ; Ornithine Carbamoyltransferase/genetics*